The present invention relates to drafting paper, and particularly to tracing paper which holds itself in place during use without the need for tacks or adhesive tape.
In order to prepare revisions or alternative versions of engineering drawings, architectural sketches, and other drawings, substantially transparent tracing paper is often used to cover an original drawing. Similarly, tracing paper is used frequently in space planning, industrial design, and generally in art and graphics. The purpose of using such tracing paper is to be able to see through the tracing paper to an original or background work, and to be able to prepare new drawings upon the transparent tracing paper sheet without disturbing the background material. Tracing paper is also used frequently to cover navigational charts while piloting in restricted waters, in order to prevent damage to charts which must be reused. In the past, such transparent tracing paper has been fastened in place using various types of adhesive tape, by using tacks or push pins, or by the use of weights to hold the tracing paper in position atop the original works.
None of the previous methods for holding tracing paper in place have been entirely satisfactory. For example, either tacks or adhesive tape can damage the original material. Tack-holes may be left, or a portion of the original material may be removed from its surface by removal of an adhesive tape, or a residue of the adhesive material may be left on the original material, where it eventually will collect dirt which damages the surface of the original material. Residual adhesive material from adhesive tapes also is likely to cling to drawing instruments, causing them to attract damaging contamination.
Weights cannot be relied upon to hold tracing paper firmly in place over the background drawing or graphic materials.
Repositioning of tracing paper originally held in position by use of tacks or adhesive tape involves laboriously removing pieces of adhesive tape from the original or background drawings or graphics materials, or removing tacks, and reapplying the adhesive tape or replacing tacks after the tracing paper has been repositioned.
The previously used adhesive tape, tacks or weights present physical obstacles to the precise use of drafting, engineering, and graphic arts tools such as templates, straight-edges, triangles, scales, drafting machines, and writing or drawing instruments. Adhesive tape, when reused, tends to lose its ability to hold materials securely, yet increasingly becomes an obstacle to the use of drafting tools and writing instruments and tends to accumulate such things such as crumbs of eraser material.
What is needed, then, is an improved manner of attachment of drafting paper or the like safely to original drawings or other graphic materials to be traced, which will hold the tracing paper securely enough in place, either initially, or after repositioning, without interfering with the use of drafting tools and writing instruments, and without collecting dirt or damaging the surface of material to which the drafting or tracing paper is attached.